The invention generally relates to systems and apparatus for lifting and loading materials into storage containers. The invention more particularly relates to an automated vehicular apparatus and method for the collection of waste materials.
In many environments, there is a need to efficiently lift and load large volumes of materials. The collection of waste materials is a good example of one such environment.
The use of curbside waste collection containers is becoming more and more widespread. In one arrangement, waste materials are accumulated by a household in plastic or metal containers. The refuse crew may empty the contents of these containers into waste collection vehicles using specially designed lifting and loading assemblies. By using these relatively large collection containers in association with specially designed lifting and loading assemblies, large volumes of waste materials can be collected in a relatively short period of time, compared to conventional hand-loading operations.
A conventional refuse collection vehicle includes a cab, a body for storing refuse positioned at the rear of the cab, and a container-handling mechanism, (such as a lift arm or boom connected to a container gripper), carried on a wheeled chassis adjacent either the cab or the body. With an automated vehicle, the container-handling mechanism is typically controllably actuated by pressurized hydraulic fluid selectively directed by controls located at the operator's compartment within the cab. Conventionally, the container-handling mechanism includes pivoting forks or opposed gripping members carried at the end of the lifting arm(s) or boom which is extendable and retractable relative to the curb or pick-up side of the vehicle. When the vehicle is brought to a stop, the lifting arm(s) and the associated fork(s) or gripping members engage the container. The container is then elevated through coordinated movement of the lifting arm(s) and/or boom and forks, for example, to position the container adjacent or over a hopper located behind the cab to deposit the refuse.
Lifting and loading mechanisms that engage the container in the front of the waste collection vehicle, known as "frontloaders", are in common use. (Throughout this application, "front" or "forward" will be used to signify the cab-end of the vehicle while "back" or "rearward" will denote the opposite direction of the vehicle.) These mechanisms conventionally have two curved arms that clear the cab in front of the vehicle, connected to a pair of pivoting forks that fit into side or bottom pockets of a steel collection container. Other conventional mechanisms employ a triangular frame in front of the cab that locks into a triangular pocket on the rear face of a collection container. Other types of collection containers can be used, as well.
Another example of a lifting assembly is shown in U.S. Pat. No. 4,715,767 to Edelhoff et. al. Edelhoff discloses a lift arm arranged to pick-up the containers along the side of the cab, generically known as a "sideloader."
Conventional refuse vehicles include a packing blade or ram to periodically compact the refuse within the storage body, permitting larger loads. The specific location of the packing blade is typically not monitored by a feedback control system. Instead, trip switches are conventionally used to detect whether a predetermined "packing point" has been reached by the the packing ram; if not, the ram is returned to its original forward or home position, and the operator is apprised of the presence of a full load by an indicator light or other means. It would be advantageous to continuously monitor the packer ram movement, and to maintain a packing pressure on the load at predetermined times, even when the packing point cannot be reached, to increase payloads.
One objective of the present invention is to provide a refuse compacting system with enhanced packing efficiency.
Another object of the present invention is to provide a refuse vehicle with a fast and efficient return-from-dump cycle.
Yet another object is to provide an automated vehicular waste system in which movement of the arms and forks is constantly monitored to avoid undesirable arm or fork motion which might damage the vehicle.
It is also an object to provide an automated refuse vehicle which can handle conventional containers, in addition to those specially designed for automated use.
Another objective is to permit the use of an automated refuse vehicle of the "frontloader" variety that is "low profile" in the sense that the lift arm does not exceed a relatively low, predetermined height "envelope" during lifting and dumping of the container.
Another objective of this invention is to provide a lifting and loading apparatus that performs all primary operations with a single control lever.
Still another objective of this invention is to provide a lifting and loading apparatus that permits the use of a conventional, unmodified cab.
Still other objects will be recognized upon reading the following disclosure.